Is my computer being hijacked?

My laptop has Windows XP with all SP's & Pathes. 1GB RAM. Since about a month ago i started to have my keyboard respond very slow and the mouse jumps around. Sometimes it acts like the mouse clicked on something when i was not even touching it. Then sometimes on occassion the system runs fine. i never see the procesor utilixzation very high and most memory is unused. CAN SOMEONE PLEASE HELP ME!

This is a laptop and i am using the keyboard & mouse on it. This minute it is working fine. But i will bet you real money within five minutes this issue will start again. It is not all the time but about 90%-95% of the time.
Thanks....

UPDATE: Less than five minutes (about two or three) an the problem started again

Update 2: Another thing i noticed which might be related. In Windows Explorer right now i can click on the file and view menu from the top but not the Edit menu. Noticed this once before.